Re: Mixing OO and DB

"Marshall" <marshall.spight_at_gmail.com> wrote in message news:b906247f-a95b-4003-8696-09d8bc43e243_at_s19g2000prg.googlegroups.com...
> On Mar 5, 6:21 am, "Brian Selzer" <br..._at_selzer-software.com> wrote:
>>
>> How is that different from denormalization? Updates still have to be
>> made
>> in a denormalized schema. Of course, instead of updating one row, it may
>> be
>> necessary to update hundreds or even thousands of rows due to the
>> redundancy
>> inherent in a denormalized schema. With a materialized view, those
>> updates
>> become a refresh of the view, which can happen independent of the update.
>> The only substantive difference I can see here is that queries can still
>> be
>> satisfied by using the base tables while the materialized view is being
>> refreshed, but with a denormalized schema, queries must be held up until
>> those hundreds or even thousands of rows are updated, assuming, of
>> course,
>> that clients need the absolute latest values.
>
> You make some good points, but there's another one you
> didn't mention, and that is that manual denormalization is more
> error prone. You have to get it right everywhere you do an
> update, and that's not just in code. Also doing it manually
> means that every relevant programmer has to know the
> protocol, and follow it without mistake, every time, instead
> of just declaring the intent and letting the computer handle it.
>

You're absolutely right.

>
> Marshall
Received on Wed Mar 05 2008 - 21:02:36 CET